Development of a CCR5-tropic HIV-1 fusion inhibition assay amenable to high-throughput screening for topical microbicides

Background The development of safe and effective topical microbicides to limit the continuing AIDS pandemic is a high priority. The current NIAID microbicide testing algorithm includes both CCR5 (R5)-tropic and CXCR4 (X4)-tropic attachment inhibition assays, and an X4-tropic fusion inhibition assay. To complete this testing algorithm, an R5-tropic fusion inhibition assay was developed. The rationale for this development was that mucosal HIV-1 infection is primarily mediated through the R5 receptor and an R5-tropic entry inhibitor should be included in combination microbicide prophylaxis.